Shocking moment American schoolgirl KNEES her opponent in the face as she lay on the field injured

An American schoolgirl footballer was caught viciously kneeing one of her opponents in the face during a game in a startling video that has set off a firestorm online this week.

In the 13-second clip, which has attracted more than 2million views since being posted on YouTube on October 12, Wood Cross High School senior-year student Makenzie Clark, dressed in a blue kit No 12, could be seen falling to the ground after tearing a ligament in her ankle during a play.

As the girl attempts to roll into a sitting position, a rival player from Salt Lake City High East, identified as No 12 Petiola Manu, pulls back her leg and slams her knee into Clark's face and then calmly walks away.

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Sports injury: Wood Cross High School player Makenzie Clark, dressed in a blue jersey No 12, tore a ligament in her ankle during the September 27 game against Salt Lake City High East

Foul act: A bystander recorded a video showing Petiola Manu, seen dressed in a white jersey No 12, approach her opponent Clark as she lay on the ground and hit her

Dirty move: Manu was caught on video viciously kneeing Clark in the face

Unpunished: Manu walked away after assaulting Clark and continued playing without getting a penalty

None of the coaches or referees witnessed the incident during the September 27 game, and no free-kick was awarded, KSL.com reported. Clark, 17, ended up being carried off the field by her team-mates.

Manu was allowed to continue the game, but she was eventually pulled out by her coach who had noticed that her emotions were running high, according to Desert News. East eventually won 2-1 in extra-time.

After the video showing Manu's unsporstmanlike conduct surfaced online, East High's principal Paul Sagers met with both his girls' football coach and Manu. The Utah High School Activities Association is investigating the foul play.

On Monday, Manu issued an apology to Clark, telling reporters, 'I let my emotions get the best of me and I took it too far. And I just want to apologize to (Makenzie) and everyone. I'm sorry.

‘It was a physical game and I let my emotions get the best of me. It was nothing personal. I was just really frustrated with the game. I wasn't thinking. I was just running on adrenaline, and the game was tied at the time.’

Mea culpa: Manu, left, later apologized to Clark, right, saying that she let her emotions get the best of her during a physical game, and that the hit was not personal

Clark's mother, Susie Clark, said the first time she saw the video, it made her sick to her stomach.

‘I just see my baby out there,’ Clark told ABC4. ‘It was a dead ball. It was after the fact. It was after the play was over. It was a brutal, dirty shot.’

Outraged: Clark's mother, Susie, said what Manu did to her daughter was unsportsmanlike and unacceptable

The player’s mother added, however,
that seeing the footage also left her feeling grateful that Manu did not
hit her daughter in the temple or broke her jaw.

'I mean, there were so many other things that could have gone wrong that were really, really lucky Makenzie was OK.'

She also said that while she is not naive about the aggressive nature of girls football, which often results in injuries and bruises, what was done to her daughter on the field went far beyond that.

‘A knee to an unprotected head is unacceptable, that kind of unsportsmanship is unacceptable, and I don't want a player to get away with this to set a precedent for it to be able to happen again, that they can get away with something,’ she said.

According to East football coach Rudy Schenk, Manu is a decent player, and she has not previously been known to get violent on the field.

The high school plans to use the video to teach athletes about the importance of sportsmanship.

The Salt Lake City incident is only the latest in a series of brutal altercations among youth soccer players which have made headlines in recent years.

In March, Annette McCullough, a senior-year student at Lewisville High in South Carolina was charged with assault after punching an opposing player repeatedly in the face during a match against Chester High School (pictured below).

Vicious: In an immediate reaction to being tripped, 18-year-old Annette McCullough
grabs her rival by her hair and rains blows down on the girl's
head